How do computers really work?

Free, playful computer science lessons for kids aged 8–10. Flip switches, store numbers in memory, race search algorithms and write real Python to guide a robot — learning the big ideas, not just how to type code.

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What is a computer?

Information goes in, instructions run, information comes out.

1 lessons

Binary

How computers count with just 0 and 1.

5 lessons

Pixels & Colours

How screens show pictures using numbers.

4 lessons

Everything is data

Numbers can stand for letters, colours and even a whole game.

2 lessons

Memory

Where computers keep things — boxes, addresses and variables.

5 lessons

Arrays

Lists of things, side by side in memory.

4 lessons

References

Variables can point at things in memory instead of holding them.

1 lessons

Game data in memory

Players, enemies and items are variables and lists, nested together.

1 lessons

Thinking in steps

Algorithms are precise steps, and big problems break into small ones.

2 lessons

Searching

Smart ways to find things fast.

5 lessons

Sorting

Clever ways to put things in order.

4 lessons

Pathfinding

How a game character finds its way.

1 lessons

Efficiency

Why some algorithms get slow as problems grow.

1 lessons

Inside the CPU

The tiny instructions a computer really runs.

3 lessons

Programming languages

Why we climb from bits up to Python.

3 lessons

Loops

Write Python to make a robot repeat itself.

4 lessons

Conditionals

Teach your programs to make decisions.

4 lessons

Functions

Make your own commands and reuse them.

4 lessons

Stack & Heap

Peek inside memory while your program runs.

4 lessons

Debugging

Be a bug detective: find and fix mistakes.

4 lessons

How the Internet works

Addresses, packets, names and web requests.

4 lessons

Online games

Lag, and who decides what really happened.

2 lessons

How apps are built

Front ends, back ends, APIs, databases and logins working together.

6 lessons

How machines learn

Examples, digits, weights and neural networks.

5 lessons

How chatbots work

Tokens, next-word prediction, attention and LLMs.

4 lessons

What makes a game

Players, goals, rules and feedback: the parts every game is built from.

1 lessons

The game loop

How a game updates and redraws itself over and over.

2 lessons

Coordinates and movement

Where things are in a game, and how they move.

2 lessons

Input and events

Keys, taps and the code that answers them.

1 lessons

Collision and physics

How games know things touched, and make them bounce and slide.

2 lessons

Game characters that think

Rules, chasing and pathfinding for non-player characters.

1 lessons

Inventories and game data

Dictionaries, item facts and how a game keeps its stuff.

1 lessons

Levels and progression

Difficulty curves, checkpoints and saving.

1 lessons

Multiplayer problems

Lost messages, and keeping everyone's game in step.

1 lessons

Game architecture

A game is a set of systems, each with one job.

1 lessons

Build your own game

Turn a big idea into a plan made of small systems.

1 lessons

AI inside programs

AI is one part of a program. The program still owns the rules.

1 lessons

Prompts are specifications

How to say exactly what you want built.

1 lessons

Code completion

AI that finishes your code, and how to check it.

1 lessons

Code generation

AI that writes whole functions, and why you still check them.

1 lessons

AI as teacher and debugger

Ask good questions, then check the answers.

1 lessons

Breaking software into parts

Turn "build a game" into pieces you can build and test.

1 lessons

Vibe coding

Idea, request, build, run, diagnose, refine.

1 lessons

AI agents

AI that plans, edits, tests and tries again, with you in charge.

1 lessons

Building a project with AI

Plan, split, build part by part, and test, with an AI helper.

1 lessons

Testing and verification

How to know that code really works.

1 lessons

Circuits

Electricity needs a loop. Build circuits with batteries, wires, bulbs and switches.

4 lessons

Volts, amps and ohms

Push, flow and squeeze: the numbers engineers use to design safe gadgets.

4 lessons

Logic gates

Circuits that make decisions: AND, OR, NOT, and a circuit that adds.

4 lessons

Transistors and chips

Switches flipped by electricity, gates and memory made from them, and what's inside a chip.

4 lessons

From breadboard to chips

Build on a realistic breadboard: LEDs, transistors, pull-down resistors and real logic chips.

5 lessons

Inputs and sensors

Buttons, dials, joysticks and sensors: how a gadget notices the world.

4 lessons

Lights, sound and motion

LEDs, screens, speakers and rumble motors: how a gadget talks back.

4 lessons

Microcontrollers

A tiny computer with pins: code that reads buttons and lights LEDs.

4 lessons

Design a gadget

Plan your own handheld game: requirements, a block diagram, a power budget, then test it.

4 lessons

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